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** The author disclaims copyright to this source code. In place of
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** a legal notice, here is a blessing:
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** May you do good and not evil.
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** May you find forgiveness for yourself and forgive others.
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** May you share freely, never taking more than you give.
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*************************************************************************
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** This file contains the sqlite3_get_table() and sqlite3_free_table()
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** interface routines. These are just wrappers around the main
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** interface routine of sqlite3_exec().
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** These routines are in a separate files so that they will not be linked
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** if they are not used.
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** $Id: table.c,v 1.36 2008/07/08 22:28:49 shane Exp $
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#include "sqliteInt.h"
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#ifndef SQLITE_OMIT_GET_TABLE
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** This structure is used to pass data from sqlite3_get_table() through
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** to the callback function is uses to build the result.
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typedef struct TabResult {
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** This routine is called once for each row in the result table. Its job
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** is to fill in the TabResult structure appropriately, allocating new
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** memory as necessary.
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static int sqlite3_get_table_cb(void *pArg, int nCol, char **argv, char **colv){
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TabResult *p = (TabResult*)pArg;
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/* Make sure there is enough space in p->azResult to hold everything
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** we need to remember from this invocation of the callback.
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if( p->nRow==0 && argv!=0 ){
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if( p->nData + need >= p->nAlloc ){
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p->nAlloc = p->nAlloc*2 + need + 1;
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azNew = sqlite3_realloc( p->azResult, sizeof(char*)*p->nAlloc );
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if( azNew==0 ) goto malloc_failed;
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/* If this is the first row, then generate an extra row containing
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** the names of all columns.
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for(i=0; i<nCol; i++){
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z = sqlite3_mprintf("%s", colv[i]);
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if( z==0 ) goto malloc_failed;
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p->azResult[p->nData++] = z;
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}else if( p->nColumn!=nCol ){
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sqlite3_free(p->zErrMsg);
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p->zErrMsg = sqlite3_mprintf(
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"sqlite3_get_table() called with two or more incompatible queries"
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/* Copy over the row data
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for(i=0; i<nCol; i++){
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int n = strlen(argv[i])+1;
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z = sqlite3_malloc( n );
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if( z==0 ) goto malloc_failed;
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memcpy(z, argv[i], n);
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p->azResult[p->nData++] = z;
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p->rc = SQLITE_NOMEM;
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** Query the database. But instead of invoking a callback for each row,
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** malloc() for space to hold the result and return the entire results
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** at the conclusion of the call.
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** The result that is written to ***pazResult is held in memory obtained
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** from malloc(). But the caller cannot free this memory directly.
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** Instead, the entire table should be passed to sqlite3_free_table() when
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** the calling procedure is finished using it.
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int sqlite3_get_table(
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sqlite3 *db, /* The database on which the SQL executes */
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const char *zSql, /* The SQL to be executed */
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char ***pazResult, /* Write the result table here */
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int *pnRow, /* Write the number of rows in the result here */
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int *pnColumn, /* Write the number of columns of result here */
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char **pzErrMsg /* Write error messages here */
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if( pnColumn ) *pnColumn = 0;
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if( pnRow ) *pnRow = 0;
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res.azResult = sqlite3_malloc(sizeof(char*)*res.nAlloc );
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if( res.azResult==0 ){
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db->errCode = SQLITE_NOMEM;
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rc = sqlite3_exec(db, zSql, sqlite3_get_table_cb, &res, pzErrMsg);
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assert( sizeof(res.azResult[0])>= sizeof(res.nData) );
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res.azResult[0] = SQLITE_INT_TO_PTR(res.nData);
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if( (rc&0xff)==SQLITE_ABORT ){
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sqlite3_free_table(&res.azResult[1]);
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sqlite3_free(*pzErrMsg);
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*pzErrMsg = sqlite3_mprintf("%s",res.zErrMsg);
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sqlite3_free(res.zErrMsg);
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db->errCode = res.rc; /* Assume 32-bit assignment is atomic */
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sqlite3_free(res.zErrMsg);
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sqlite3_free_table(&res.azResult[1]);
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if( res.nAlloc>res.nData ){
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azNew = sqlite3_realloc( res.azResult, sizeof(char*)*(res.nData+1) );
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sqlite3_free_table(&res.azResult[1]);
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db->errCode = SQLITE_NOMEM;
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res.nAlloc = res.nData+1;
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res.azResult = azNew;
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*pazResult = &res.azResult[1];
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if( pnColumn ) *pnColumn = res.nColumn;
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if( pnRow ) *pnRow = res.nRow;
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** This routine frees the space the sqlite3_get_table() malloced.
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void sqlite3_free_table(
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char **azResult /* Result returned from from sqlite3_get_table() */
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assert( azResult!=0 );
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n = SQLITE_PTR_TO_INT(azResult[0]);
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for(i=1; i<n; i++){ if( azResult[i] ) sqlite3_free(azResult[i]); }
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sqlite3_free(azResult);
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#endif /* SQLITE_OMIT_GET_TABLE */